Passenger Takes Over Cirrus for Incapacitated Pilot

Way to go chica!

It really is amazing what hypoxia can do to a person.

Yes, hypoxia is a problem for even us GA pilots flying at mid altitudes.  The CFR's, which don't even require oxygen till 12000 feet, don't take into account that most of us start getting hypoxic at around 9000-10000 feet (I know I do!).  We also frequently forget that many things can reduce our hypoxia tolerance such as smoking, illness, some medications, lack of physical conditioning, age, fatigue and plenty others.  It is important to know your hypoxia signs so you can respond quickly if you begin to have them.  Hypoxia training is readily available through the FAA and more than a few commercial companies.  A new type of training does not require the use of a "chamber" and is also available usually for a fee.  I am attaching an easy to read article on hypoxia if anyone is interested in learning more about the subject.  Gregory Pinnell, MD EAA Aeromedical Council

Thanks for posting Greg (although I think "new" is a little bit of a stretch given this article is from 2005).

One question I have had regarding the Oxygen reduction method instead of "chamber" method is: How much of an affect does the lower pressure have on the indivuals symptoms?  I understand how you can get the feeling/understnading of your individual hypoxia symptoms by just reducing the oxygen.  However, if you are training pilots to identify their symptoms, wouldn't it be more prudent to get the envirnment as close to realistic as possible?

Another way to ask my question(s) is: What are the pros and cons of using the reduced oxygen method vs the chamber method?

Is there a list of recommended locations around the country that offer the training?  What are the typical fees involved?  Is it less than renting an oxygen bottle, instructor, and airplan for an hour?

Sorry for all of the questions...you just look like a good person to ping about some of this stuff.

Thanks in advance!

Great questions.  I can only tell you from my own experience of doing a "chamber" 4 times and doing mixed gas twice now.  I don't think the lower pressure made much of a difference.  I developed the same hypoxic symptoms with the mixed gas trial as I did in the chamber.  I don't know if there is a list or not at this point of the normobaric testing sites.   We are working on getting one at Western Michigan College of Aviation but I think Embry Riddle has one.  I know the FAA is looking at them and did a recent field trial on one with the acronym "PROTE).  I know when I am flying high altitude (well at least 12000 is high in my Cherokee Six)  I use a medical E cylinder with a stock regulator.  I never have a hard time keeping my O2 saturation above 95% on my pulse oximeter.  Hope that helps!  Greg

Thanks Greg.

I know I don't want to be the guy, but if someone were to do an around the country "hypoxia-storming" event at various sites around the country, I would participate in one that was close.

Either that or maybe a hypoxia training groupon or something...

I suppose that could be done as some of the equipment is portable (the mask version).  But there is liability involved as when you test enough people even with screening you are going eventually have a bad reaction.  Thats where the medical supervision comes in. Take care.

I took "chamber" testing with Uncle Sam's Air Force back in the late 60's and it made a big impression on me.  In those days Air Force regulations required the use of oxygen by all crew members at 10,000MSL and above.  I do believe you can get familiar with the symptoms of oxygen starvation without a chamber.  We got rapid decompression experience along with the hypoxia with the chamber.  The basic warning signs are blue lips and fingertips followed by a deterioration of peripheral vision , then tunnel vision to black-out.  During this progression you get light headed and acquire the attitude of a "happy drunk".  I still remember this after 40 plus years and I'd bet Greg can add a bit more to this.

Joe

Now here's a question I have asked several times at AOPA and EAA and never got an answer.  Maybe these Bloggers can help me. Question: what's the influence of density altitude on hypoxia?  We all learn that density altitude robs us of engine power, lift capacity, etc.  Suppose that, on a warm/hot day, your 2000' MSL airport acts like it is at 5000'.  So I 'loose' 3000'; also when the A/C's ceiling was normally, say 13000', it now will be 10000' (because the airplane 'thinks' or behaves like it is at 13000').

Back to the question: if I feel normally 'groggy', I mean in this case feeling the effects of hypoxia, at 13000', will I now feel the same at 10000'?  If that is so, then all oxygen laws need to have this caveat included; example: use oxygen at 12500' under standard day conditions; change that altitude according the density altitude. I mean, if my engine can not 'breathe' anymore, the human body should respond the same, no?   I repeat that I have asked this question to people like Barry Schiff, Jonathan Sackier, Rod Machado and others and I never got a direct response; the responses varied from "you are confusing pressure with density" (and if so, what's the effective difference?) to "interesting question; look for a future column on this", etc.  Who can answer me with a real explicative answer?  Thank you.

Bob,

I am no expert, but my guess would be that it's such a broad answer because everyone acts differently.  The rule was probably put into place to simply start reminding people about oxygen at a certain level.  As we have discussed, some people are fine up to very high altitudes, and some people have trouble at 10K.  Therefore the rule is more of a "guidline" and if there is an even streaming from lack of oxygen, they are going to nail you with one of the general rules such as the pilot did not have enough information to safely conduct his flight (he didn't know about his body's respons to hypoxia) or 2, you were being careless (by getting to close to the oxygen limits whitout knowing your body's reaction), etc.

This is just another one of those rules they have no way to enforce (unless a passenger complains), nor would they really care if all is well.

Just my $0.02

That is an interesting question and I am not sure it has been studied.  I can check with the research people if you really want to see if this has been looked at.  I usually don't pay attention to anything more than what my pulse ox is showing.  If I am around 90% I start to get fuzzy.  I do know that I have been in the chamber at 25000 feet and felt fine for quite some time before putting my mask back on.  I also know that on a winters day at 9000 feet I start to get my first hypoxic symptoms.  Alot of variables.  Greg